Tracking cardio activities separately from generic strain in My Plan

I would like to be able to set cardio activities in my weekly plan as either running or inline skating, for instance. The only way to do this currently, as far as I know, would be to set a total number of weekly activities with X number of cardio activities added to other activities such as strength training, but I find it hard for me to be consistent enough for this method to be useful. To be clear, I’m not asking for automatic detection of cardio activities vs other types of activities since I manually log my cardio.